US3303345A - Image amplifier with magnification grid - Google Patents

Image amplifier with magnification grid Download PDF

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Publication number
US3303345A
US3303345A US325297A US32529763A US3303345A US 3303345 A US3303345 A US 3303345A US 325297 A US325297 A US 325297A US 32529763 A US32529763 A US 32529763A US 3303345 A US3303345 A US 3303345A
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US
United States
Prior art keywords
anode
image
photocathode
screen
cathode
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US325297A
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English (en)
Inventor
W Christiaan Jacobus Hubertus
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
US Philips Corp
North American Philips Co Inc
Original Assignee
US Philips Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by US Philips Corp filed Critical US Philips Corp
Application granted granted Critical
Publication of US3303345A publication Critical patent/US3303345A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J31/00—Cathode ray tubes; Electron beam tubes
    • H01J31/08—Cathode ray tubes; Electron beam tubes having a screen on or from which an image or pattern is formed, picked up, converted, or stored
    • H01J31/50—Image-conversion or image-amplification tubes, i.e. having optical, X-ray, or analogous input, and optical output
    • H01J31/501—Image-conversion or image-amplification tubes, i.e. having optical, X-ray, or analogous input, and optical output with an electrostatic electron optic system
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
    • B23B—TURNING; BORING
    • B23B13/00—Arrangements for automatically conveying or chucking or guiding stock
    • B23B13/12—Accessories, e.g. stops, grippers
    • B23B13/126—Supports
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
    • B23Q—DETAILS, COMPONENTS, OR ACCESSORIES FOR MACHINE TOOLS, e.g. ARRANGEMENTS FOR COPYING OR CONTROLLING; MACHINE TOOLS IN GENERAL CHARACTERISED BY THE CONSTRUCTION OF PARTICULAR DETAILS OR COMPONENTS; COMBINATIONS OR ASSOCIATIONS OF METAL-WORKING MACHINES, NOT DIRECTED TO A PARTICULAR RESULT
    • B23Q1/00—Members which are comprised in the general build-up of a form of machine, particularly relatively large fixed members
    • B23Q1/25—Movable or adjustable work or tool supports
    • B23Q1/44—Movable or adjustable work or tool supports using particular mechanisms
    • B23Q1/50—Movable or adjustable work or tool supports using particular mechanisms with rotating pairs only, the rotating pairs being the first two elements of the mechanism
    • B23Q1/52—Movable or adjustable work or tool supports using particular mechanisms with rotating pairs only, the rotating pairs being the first two elements of the mechanism a single rotating pair
    • B23Q1/527—Movable or adjustable work or tool supports using particular mechanisms with rotating pairs only, the rotating pairs being the first two elements of the mechanism a single rotating pair with a ring or tube in which a workpiece is fixed coaxially to the degree of freedom
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16C—SHAFTS; FLEXIBLE SHAFTS; ELEMENTS OR CRANKSHAFT MECHANISMS; ROTARY BODIES OTHER THAN GEARING ELEMENTS; BEARINGS
    • F16C19/00—Bearings with rolling contact, for exclusively rotary movement
    • F16C19/22—Bearings with rolling contact, for exclusively rotary movement with bearing rollers essentially of the same size in one or more circular rows, e.g. needle bearings
    • F16C19/44—Needle bearings
    • F16C19/46—Needle bearings with one row or needles
    • G—PHYSICS
    • G04—HOROLOGY
    • G04D—APPARATUS OR TOOLS SPECIALLY DESIGNED FOR MAKING OR MAINTAINING CLOCKS OR WATCHES
    • G04D3/00—Watchmakers' or watch-repairers' machines or tools for working materials
    • G04D3/02—Lathes, with one or more supports; Burnishing machines, with one or more supports
    • G04D3/0209—Components
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16C—SHAFTS; FLEXIBLE SHAFTS; ELEMENTS OR CRANKSHAFT MECHANISMS; ROTARY BODIES OTHER THAN GEARING ELEMENTS; BEARINGS
    • F16C2322/00—Apparatus used in shaping articles
    • F16C2322/39—General buildup of machine tools, e.g. spindles, slides, actuators

Definitions

  • the usual construction of an electron-optical image amplifier comprises a photoelectric cathode, an anode and a fluorescent screen which, in the said sequence are provided in a closed vessel from which the air has been removed.
  • the photo-cathode is accessible from without for radiation which, by the properties of the photo-electric cathode, is converted into electron emission.
  • an image of a considerably larger brightness can be obtained as a result of the conversion.
  • the electrons emitted by the photo-cathode are focused electron-optically on the fluorescent screen in a manner such that a reduced image of the photo-cathode is formed on the fluorescent screen.
  • the simplest electron-optical device for this purpose comprises a concave conical photo-electric cathode, a thimble-shaped anode provided at some distance therefrom, in the top of which anode an aperture is provided for passing electrons which move from the cathode to the fluorescent screen provided beyond the anode, and a conductive surface which surrounds the space between the cathode and the anode.
  • Such a system reproduces an electron-optical reduced image of the photo-cathode on the fluorescent screen.
  • the electrons are accelerated in the direction of the fluorescent screen.
  • the paths of the electrons are under the influence of the equipotential planes of the electric field between the anode and the cathode which are substantially spherical and vary slightly when the voltage varies.
  • the choice of the voltage substantially has no influence on the size of the image and the definition of the image but the brightness of the image is determined by it indeed.
  • the definition of the image may be adjusted by a potential difference between the photo-cathode and the conductive surface.
  • Image amplifiers which comprise an electronoptical system consisting of several electrodes and in which a number of metal cylindrical electrodes is arranged between the anode and the cathode.
  • the electrodes viewed from the cathode usually have ever smaller diameters and are arranged one behind the other coaxially.
  • the principal object thereof is to avoid charging of the wall when a glass envelope is used.
  • By choosing given voltages for each of the electrodes it is possible to influence the field distribution between the cathode and the anode and some variation in the size of the image may be produced.
  • the advantage that the size of the image is not only determined by the geometry of the optical system but also by the electrode voltages is outweigher by the increase of the difficulties which are experienced during the manufacture of such a system which, as a result, is
  • the object of the invention is to vary in a simple manner the size of the image, it being possible to choose between two fixed values of the magnification when using an image amplifier the electrode system of which consists of a spherical cathode, an anode and a conductive surface which surrounds the space between the anode and the cathode.
  • an electrostatic screen is provided in the electron accelerating space at a distance from the anode which is small compared with the distance between the anode and the cathode.
  • an electrostatic screen is provided having an aperture the center of which lies on the optical axis.
  • the screen takes the place of an equipotential plane determined by the potential distribution between the anode and the cathode.
  • the screen has a shape corresponding to and the same voltage as either that of the equipotential plane or the anode voltage.
  • Another feature of the invention is that in a device which is provided with such an image amplifier and a direct voltage source with connections for a high and an intermediate voltage, the latter is determined by the potential of the equipotential plane which coincides with the curved screen in the image amplifier if between the anode and the cathode the high voltage is operative, a switch effecting the connection of the intermediate voltage or the connection of the high voltage to the screen.
  • the wall of the amplifier housing consists of glass and comprises a cylindrical part 1 with a spherical closure 2 at the one end. The other end is closed by a somewhat curved bottom 3. It is not necessary that all these parts be manufactured from glass.
  • the cylinder jacket 1 may consist of metal. Such a wall renders the use of a focusing electrode 4, which, in the figure, is provided inside the cylindrical wall, superfluous. If the image amplifier is intended for X-ray investigation, the spherical end wall 2 may be made from metal which only absorbs X-rays slightly, preferably aluminum.
  • the cylinder wall 1 must be connected to it in an air-tight manner but it must also be suitable for connecting the glass bottom 3 by sealing, at least to provide glass parts in an air-tight manner which are required for the sufficient insulation of current conductors which have a high electric voltage with respect to the metal wall.
  • a voltage is supplied to the anode 5.
  • the anode consists of a cylinder 6, a conical part 7 and a spherical top 8 which are all made from metal.
  • the cylindrical part 6 is clamped around a reentrant part 9 and the top of the anode includes an aperture 10.
  • the current supply wire 11 connects the cylinder 6 to a conductor 12 through the wall 13 which encloses the re-entrant part 9.
  • This wall part 13 is a spout at the bottom 3.
  • the re-entrant part is closed by a transverse wall 14.
  • a fluorescent screen 15 is located on the inside of the transverse wall 14 in a field-free space consisting of a thin layer of fluorescent material on a transparent carrier, for example mica or glass.
  • the carrier may also be omitted and the transverse wall 14 coated with a thin layer of fluorescent material.
  • the surface of the transverse wall must be entirely flat and smooth so that it may be more advantageous to manufacture the fluorescent screen separately.
  • wires 16 are sealed in the glass and connected to the focusing electrode 4.
  • One wire service as a current conductor for supplying voltage to the electrode 4.
  • a wire 17 also sealed in the wall section 2 serves as a current conductor and is connected to the photo-electric cathode 18.
  • Photo-electric cathodes for image amplifiers which are used for X-ray tests and such in image amplifiers for other purposes, which are termed luminoscopes, are well-known.
  • the dish 18 shown in the drawing represents the one or the other photo-cathode.
  • the connection is effected by an insulating edge 19 which connects the dish 18 along the circumference to an inwardly bent edge 20 of the focusing electrode 4.
  • This electrode 4 also at the other end comprises an inwardly bent edge 21 which part also serves for checking the charging of the glass wall.
  • the anode is brought at a sufficiently high positive potential with respect to the cathode 18 (a suitable voltage is 25 kv.), the electrons emerging from any point of the cathode surface are conducted to the anode in the form of a beam.
  • a suitable voltage is 25 kv.
  • these electrons impinge upon the fluorescent screen 15 at the same point which is the image point of the point of the cathode 13 from which the electron beam has started. In this manner each emitting point of the cathode finds an image point on the luminescent screen.
  • the electron beams intersect in the proximity of the aperture in the anode 5.
  • the sliding contact 27 of a potentiometer resistor 28 which is connected between the positive and the negative terminals 23 and 24 of the current source 22 is connected to the focusing electrode 4 by the wire 26.
  • the potential of this electrode is controllable with respect to the cathode 18 and is adjustable, for example, between 0 and 200 volts and serves for focusing the greatest definition with which the image appears on the luminescent screen. For correct focusing, an image is produced on the fluorescent screen in which each part corresponds to a portion of the image on the surface of the photocathode.
  • a conductive surface formed according to a given equipotential plane is provided with an aperture for passing the electrons and connected to a voltage which has no influence on the potential distribution between the anode and the cathode, the reproducing power of the electrode system experiences no variation.
  • a conductive surface is the curved screen 29 provided in the proximity of the anode 5.
  • the aperture St ⁇ in this screen is chosen to be larger than the aperture 15) in the top of the anode.
  • the screen 29 is supported by a number of supporting rods 31 which are sealed in the bottom 3 and one of which is connected to the switching arm 33 of a switch by a wire 32. When the amplifier is in normal use, the screen 29 is non-operative.
  • the screen is approximately in the position of the potential plane which corresponds to 10 kv.
  • the distance between the anode top 8 and the screen 29 will be somewhat less than the radius of the anode sphere. From calculations of accurately spherically-symmetric systems of cathode and anode, the position and the potential of the screen can readily be derived, although the exact shape and the arrangement of the screen can only be determined experimentally.
  • the object of the annular fold 35 in the bottom 3 is to increase the insulation length between the supporting wires 31 and the part of the wall where the distance to the focusing electrode 4 is small.
  • An electron optical image amplifier comprising an envelope, a concave spherical photocathode for producing an electron image corresponding to an optical image, a thimble-shaped anode within said envelope spaced from said photocathode, said thimble-shaped anode having an aperture therein for the passage of electrons emanating from the photocathode resulting from light incident thereon, a fluorescent screen positioned to receive electrons passing through the aperture in the anode for converting the electron image into a visible image, a conductive wall surrounding the space between the photocathode and the anode, means to apply potentials to said photocathode, anode and conductive wall whereby electrons produced by the photocathode are focussed at the fluorescent screen, an electrostatic screen positioned between and closer to the anode than the photocathode, said electrostatic screen having an aperture therein the center of which lies on an optical axis extending between said photocathode and said fluorescent screen, said electrostatic screen being coinciden
  • An electron-optical image amplifier as claimed in claim 1 in which the means to apply a potential to the electrostatic screen includes switch means to connect the electrostatic screen to a potential equal to the potential of the equipotential plane at the position of the screen 3.
  • An electron-optical image amplifier as claimed in claim 1 in which the conductive wall surrounding the 6 space between the photocathode and the anode constitutes a portion of the envelope.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Image-Pickup Tubes, Image-Amplification Tubes, And Storage Tubes (AREA)
US325297A 1962-12-20 1963-11-21 Image amplifier with magnification grid Expired - Lifetime US3303345A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
NL62286999A NL144089C (nl) 1962-12-20 1962-12-20 Elektronenoptische beeldversterkerinrichting, alsmede elektronenoptische beeldversterkerbuis.

Publications (1)

Publication Number Publication Date
US3303345A true US3303345A (en) 1967-02-07

Family

ID=19754298

Family Applications (1)

Application Number Title Priority Date Filing Date
US325297A Expired - Lifetime US3303345A (en) 1962-12-20 1963-11-21 Image amplifier with magnification grid

Country Status (7)

Country Link
US (1) US3303345A (de)
AT (1) AT242206B (de)
DE (1) DE1279237B (de)
FR (1) FR1378498A (de)
GB (1) GB1013019A (de)
NL (1) NL144089C (de)
SE (1) SE314750B (de)

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3474275A (en) * 1966-09-26 1969-10-21 Rca Corp Image tube having a gating and focusing electrode
US3480782A (en) * 1967-11-01 1969-11-25 Fairchild Camera Instr Co Electronic image-intensifying tube
US3675027A (en) * 1969-10-03 1972-07-04 Shimadzu Corp System for continuously varying the size of the field of an x-ray image intensifier tube
US3683194A (en) * 1969-10-03 1972-08-08 Varian Associates Electron optics for a minifying image tube
US3835314A (en) * 1973-03-05 1974-09-10 Machlett Lab Inc Intensifier radiographic imaging system

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2700116A (en) * 1950-02-11 1955-01-18 Edward E Sheldon Device for intensification of X-ray images
US2702355A (en) * 1948-02-26 1955-02-15 Centre Nat Rech Scient Adjustable voltage glow discharge device
US2757293A (en) * 1951-09-26 1956-07-31 Hartford Nat Bank & Trust Co Luminoscope

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2955219A (en) * 1959-02-16 1960-10-04 Rauland Corp Electron discharge device

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2702355A (en) * 1948-02-26 1955-02-15 Centre Nat Rech Scient Adjustable voltage glow discharge device
US2700116A (en) * 1950-02-11 1955-01-18 Edward E Sheldon Device for intensification of X-ray images
US2757293A (en) * 1951-09-26 1956-07-31 Hartford Nat Bank & Trust Co Luminoscope

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3474275A (en) * 1966-09-26 1969-10-21 Rca Corp Image tube having a gating and focusing electrode
US3480782A (en) * 1967-11-01 1969-11-25 Fairchild Camera Instr Co Electronic image-intensifying tube
US3675027A (en) * 1969-10-03 1972-07-04 Shimadzu Corp System for continuously varying the size of the field of an x-ray image intensifier tube
US3683194A (en) * 1969-10-03 1972-08-08 Varian Associates Electron optics for a minifying image tube
US3835314A (en) * 1973-03-05 1974-09-10 Machlett Lab Inc Intensifier radiographic imaging system

Also Published As

Publication number Publication date
NL144089C (nl) 1975-04-15
DE1279237B (de) 1968-10-03
GB1013019A (en) 1965-12-15
AT242206B (de) 1965-09-10
SE314750B (de) 1969-09-15
NL286999A (nl) 1965-02-25
FR1378498A (fr) 1964-11-13

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